E-Cigarette And NRT Study

Does use of e-cigarettes and/or nicotine replacement therapy to replace regular cigarettes reduce intake of harmful materials? 

Here is a paper, conclusion from the abstract:

CONCLUSION:

Former smokers with long-term e-cigarette-only or NRT-only use may obtain roughly similar levels of nicotine compared with smokers of combustible cigarettes only, but results varied. Long-term NRT-only and e-cigarette-only use, but not dual use of NRTs or e-cigarettes with combustible cigarettes, is associated with substantially reduced levels of measured carcinogens and toxins relative to smoking only combustible cigarettes.

So, using e-cigarettes or NRT alone results in roughly the same nicotine intake but reduced carcinogens and toxins, which is good.  Using both e-cigarettes and NRT does not seem to lead to a reduction.  If you are a smoker, discuss with your physician; these results suggest to me to use either replacement but not both.  Of course, my father quit “cold turkey” which if you can do it, reduces intake of these substances to zero.  Best yet: do not start smoking to begin with, if you have not already done so.